CCPC网赛，HDU_5832 A water problem

Problem Description

          Two planets named Haha and Xixi in the universe and they were created with the universe beginning.
          There is 73 days in Xixi a year and 137 days in Haha a year.
          Now you know the days N after Big Bang, you need to answer whether it is the first day in a year about the two planets.

Input

          There are several test cases(about 5 huge test cases).
          For each test, we have a line with an only integer N(0≤N), the length of N is up to 10000000.

Output

          For the i-th test case, output Case #i: , then output "YES" or "NO" for the answer.

Sample Input

         10001

            0

         333

Sample Output

Case #1: YES

Case #2: YES

Case #3: NO

代码如下：

#include<cstdio>
#include<cstring>
#define N 10000001
char s[N];
int main()
{
    long long mod;
    int len;
    int n=10001;
    int kk=1;
       while(scanf("%s",s)!=EOF)
       {
           len=strlen(s);
           mod=0;
           for(int i=0; i<len; i++)
           {
               mod=mod*10+s[i]-'0';          
               mod=mod%n;                      
           }
           if(mod==0){
               printf("Case #%d: YES
",kk);
           }else{
               printf("Case #%d: NO
",kk);
           }
           kk++;
       }

    return 0;
}

题目大意：

          一个星星一年73天，一个星星一年137天。给你一个天数，问两者是不是恰好都是第一天。

思路解析：

         这题思路并不难想，就是求对73*173=10001取余是不是为0。这道题的坑就在大数的计算上。大数的取余计算，直接套模板。

（P.S:= =好累啊 下午5个小时 感觉身体被掏空。更一道下午的题算了，睡了睡了233333。）